PureImage Background Remover: third-party components ===================================================== PureImage Background Remover (Offline Batch Edition and the free web page) is made by Karelia Labs. It includes the components below. Each is used under its own licence; the full texts ship in the `licenses` folder next to this file. Checked on 9 November 2026. 1. BiRefNet_lite (the background-removal model) ----------------------------------------------- What: the BiRefNet_lite segmentation model (Swin-T backbone), ONNX export, half precision (fp16). Licence: MIT. Exact source used: - Hugging Face repository onnx-community/BiRefNet_lite-ONNX, revision de15b22ba131738a16dff04aab8bdf8dc32e3ac1 (last modified 2025-10-26), file onnx/model_fp16.onnx, 114,538,221 bytes, SHA-256 d39b897ceb16ae654c1731f3dba0cf9b368d9cae74b5a57459b455cc8bfec402. https://huggingface.co/onnx-community/BiRefNet_lite-ONNX/resolve/de15b22ba131738a16dff04aab8bdf8dc32e3ac1/onnx/model_fp16.onnx - Its model card declares `license: mit` and `base_model: ZhengPeng7/BiRefNet_lite` (https://huggingface.co/onnx-community/BiRefNet_lite-ONNX). - The base model card https://huggingface.co/ZhengPeng7/BiRefNet_lite (revision aa62cd87eafb9cc43056d08ef3615a14628b831d) also declares `license: mit`. - The code repository https://github.com/ZhengPeng7/BiRefNet is MIT licensed (GitHub licence API: MIT, LICENSE blob 485921e8271834871ff2baafb892b79ef6a75e75, 4,382 stars, last push 2026-10-25). Changes made by Karelia Labs: the ONNX graph was rewritten so it fits in a browser (tools/prepare_model.py). The weights are byte-for-byte the originals. Each deformable convolution is computed in bands of rows instead of all at once, and wide Split/Concat nodes are split into trees. Output on a test image differs from the original file by at most 0.0025 (alpha 0..1), which is float16 rounding. Licence text (from https://github.com/ZhengPeng7/BiRefNet/blob/main/LICENSE): MIT License Copyright (c) 2024 ZhengPeng Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. Not used, on purpose: ISNet ONNX (AGPL-3.0 per its model card), BRIA RMBG (non-commercial licence), the IMG.LY background-removal library (AGPL). 2. ONNX Runtime Web 1.30.0 (runs the model) ------------------------------------------- What: onnxruntime-web 1.30.0 from npm: dist/ort.webgpu.min.js, dist/ort-wasm-simd-threaded.asyncify.mjs and dist/ort-wasm-simd-threaded.asyncify.wasm (WebGPU with a WebAssembly CPU fallback). Licence: MIT, Copyright (c) Microsoft Corporation. Exact source used: - https://registry.npmjs.org/onnxruntime-web/-/onnxruntime-web-1.30.0.tgz (npm integrity sha512-q0y+JrrtukXSzsBWEMccVfqX25LRmosXHF+CaRJmg8pZClzcV7svNc4rKY3jL02Vb7QmRMDs1SigqR4CXAfKYQ==, verified after download; package.json "license": "MIT"). - Licence text: https://github.com/microsoft/onnxruntime/blob/v1.30.0/LICENSE - Third-party notices of ONNX Runtime itself (compiled into the .wasm file): https://github.com/microsoft/onnxruntime/blob/v1.30.0/ThirdPartyNotices.txt, shipped as licenses/ThirdPartyNotices-onnxruntime.txt. It lists permissive licences (MIT, BSD, Apache-2.0) and Eigen under MPL-2.0. Eigen's source is available at https://gitlab.com/libeigen/eigen and the ONNX Runtime source that pins it at https://github.com/microsoft/onnxruntime/tree/v1.30.0. Mbed TLS is listed as Apache-2.0 OR GPL-2.0-or-later and is used under Apache-2.0. Licence text: MIT License Copyright (c) Microsoft Corporation Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. The free web page loads the same three files from https://cdn.jsdelivr.net/npm/onnxruntime-web@1.30.0/dist/ and checks their SHA-256 before use. 3. Fonts -------- - Inter Tight (variable, latin and latin-ext): SIL Open Font License 1.1, Copyright 2022 The Inter Project Authors (https://github.com/rsms/inter-tight). Taken from the @fontsource-variable/inter-tight npm package. Text: licenses/OFL-InterTight.txt. - Fragment Mono 400 (latin): SIL Open Font License 1.1, Copyright 2022 The Fragment-Mono Project Authors (https://github.com/weiweihuanghuang/fragment-mono). Taken from @fontsource/fragment-mono 5.3.0 (npm). Text: licenses/OFL-FragmentMono.txt. Both are embedded in the stylesheet, so nothing is fetched from a font service. 4. PureImage metadata engine ---------------------------- app/pure-engine.js is PureImage's own metadata engine (the one used on pureimage.online), by Karelia Labs.